The present invention relates to a ground water drain for covering a ground opening and which comprises a frame laid in the ground and a grating supported on a frame support. The grating is made from a material with elastic properties and is insertable in the frame utilizing the elasticity. The grating is held in the frame with a positive fastening.
Ground water drains and, in particular, the gratings thereof have hitherto been manufactured in such a way that they constitute a relatively rigid structure, which is inserted in the frame. As a result of the relatively high dimensional stability of such gratings, the traffic travelling over the gratings has not been able to deform the gratings and, as a result, they could possibly jump out of the frame.
However, covers and gratings for ground water drains have been increasingly used, which have a lighter construction, because they are made from a material with a greater strength than typical cast iron and have a greater elasticity than the latter. Therefore the traffic travelling over the grating is able to elastically deform the latter, so that it is tensioned in much the same way as a spring and when the tension is removed it can deform to such an extent that it jumps out of the frame. Another disadvantage is that the presently used covers are provided with gratings, which can be relatively easily removed from the support located in the frame.
A ground water drain is known (DE No. 28 11 961), which is made from an elastic material and in which the grating bars are interconnected at their ends by spacers, in such a way that the complete grating constitutes an elastic structure. For the positive fastening of such a grating in the frame, it is known to provide holding parts on the front faces of the grating. The holding parts are hooked in corresponding frame parts, bringing about a positive connection between the grating and the frame. However, it is disadvantageous that the complete grating forms an elastic structure, which is elastically tensioned and relieved by the traffic travelling over it. Therefore, despite the positive fastening, as a result of its overall elasticity, the grating can jump out of the frame or can be relatively easily removed from the latter.
Gratings are known, in which special parts are constructed with increased elasticity and form a positive connection with corresponding parts in the frame. Admittedly with this grating there is no risk of jumping out, but the special construction of the elastic elements weakens the frame, and manufacturing costs are also increased.